You surely noticed how low gas prices were this winter, and you're probably pleasantly surprised that they're still low. You might be thinking - this can't last forever, can it? Gas will probably be $4/gallon this summer, right?

According to GasBuddy, it won't. The projected average price of gas for this summer is a cool $2.76/gallon.

There's no better way to take advantage of this than to make 2015 the year of the road trip. Here's a little perspective on how 2015's fuel prices compare to previous summers.

Average Savings On Road Trips, 2014 vs. 2015

Below are some examples of how much you'll save on a road trip this year compared to last. For our starting destination, we used Chicago because it's centrally located and it's also where Brads Deal's HQ is based. To calculate estimated fuel cost from your city, use this formula:

Distance (mi) / Your car's MPG = Gallons of fuel needed

Gallons of fuel X $2.76 = estimated fuel cost

Chicago to Yellowstone: $312 ($105 cheaper than last year)

Chicago to Washington D.C.: $153 ($52 cheaper than last year)

Chicago to Great Smoky Mountains: $127 ($43 cheaper than last year)

Chicago to Grand Canyon: $365 ($122 cheaper than last year)

NOTE: This data assumes 25 MPG for the hypothetical vehicle, which is that national average per AAA.

Buy a National Parks Pass

So, you're saving 25 percent on gas by taking your cross-country road trip this year, but that's not the only way to save money on your 2015 summer vacation.

If you plan on hitting several parks on your trip, it might make sense to buy a yearly pass. A pass is $80 and is charged on a per-vehicle basis. For most parks, admission is around $25 per vehicle, so it'll pay off if you plan on visiting four or more parks within 365 days of buying your pass.

Deeply discounted access passes are available to seniors for $10, and any U.S. resident over 62 can obtain a lifetime pass. Military members and their dependents can obtain a free yearly pass. Learn more at NPS.gov.

Keep in mind that of the 407 National Parks in the system, only 127 charge admission, so you may not need the yearly pass if you visit the free ones. However, the most popular parks typically charge for entry. More information on this is available here.

Take Advantage of Free Days

The National Parks Service has a number of free days throughout the year. Keep in mind that parks will likely be very busy on these days. If you can handle the larger crowds, free days are a great way to add to your fuel savings and make your road trip truly frugal.

Martin Luther King Jr. Day (third Monday in January)

Presidents' Day Weekend

April 18-19 (opening weekend of National Park Week)

August 25 (National Park Service Birthday)

September 26 (National Public Lands Day)

November 11 (Veterans Day)

The National Parks Service is also running a promotion called "Every Kid In A Park," which will allow 4th grade students and their families to gain free entry into National Parks for the 2015-2016 school year. The passes have yet to go live, but you can sign up for more information and learn more about the program here.

If you're planning a road trip to a National Park this summer, we want to hear about it! Make sure to post a picture to our Facebook page when you get there. Happy road tripping, Brad's Dealers!

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